Arms · Beginner
AI Bicep Curl Counter
The bicep curl is the classic arm-builder: bend at the elbow, lift the weight, squeeze. It needs almost no space and works with dumbbells or anything you can hold. REP RUSH watches through your webcam and counts every clean curl — including hammer curls and other variations — so you can focus on the squeeze instead of the tally.
- In the app
- Counted for you
- Muscles worked
- Biceps brachii, Brachialis, Forearms (brachioradialis)
- Equipment
- Dumbbells (or any weight — water bottles work)
- Also called
- dumbbell curls, hammer curls, arm curls, biceps curls
How to do bicep curls with proper form
- 1 Set up. Stand tall with feet hip-width apart, a weight in each hand, arms hanging straight and palms facing forward.
- 2 Lock your elbows. Keep your elbows tucked against your sides and your upper arms still — they shouldn't swing.
- 3 Curl up. Bend at the elbow to lift the weights toward your shoulders, and squeeze your biceps at the top.
- 4 Lower under control. Slowly straighten your arms all the way back to the start. That's one rep.
Popular variations
Hammer curls
Turn your palms to face each other (thumbs up) and curl. This neutral grip hits the brachialis and forearms harder, and it's easier on the wrists. REP RUSH counts hammer curls the same as standard curls — just curl one arm at a time.
Concentration curls
Sit down, brace your elbow against your inner thigh, and curl one arm at a time. Removing momentum makes this one of the strictest ways to isolate the biceps.
Reverse curls
Curl with your palms facing down. This shifts the work toward the forearms and the top of the biceps, and builds grip strength as a bonus.
Muscles worked
Primary
Biceps brachii
Supporting
Brachialis, Forearms (brachioradialis)
Common mistakes
Swinging the weight
Using your hips and back to heave the weight up. Slow down and let the biceps do the work.
Moving your elbows
Letting elbows drift forward or flare out. Pin them to your ribs so the motion stays at the elbow joint.
Half reps
Not straightening your arms at the bottom. Full range of motion gives full results.
Dropping the weight
Rushing the lowering phase. Controlling the way down builds just as much muscle as lifting up.
How many reps & sets
For size and strength, do 3–4 sets of 8–12 reps with a weight that's challenging by the last couple of reps. For endurance, go lighter for 2–3 sets of 15–20. Rest 60–90 seconds between sets and train biceps 2–3 times a week, not every day — muscles grow during recovery.
Bicep Curls FAQ
What muscles do bicep curls work?
Curls primarily target the biceps brachii on the front of your upper arm, with help from the brachialis and forearm muscles. Hammer and reverse curls shift more of the work onto the brachialis and forearms.
Does REP RUSH count hammer curls?
Yes. REP RUSH counts the curling motion whether your palms face up (standard curl) or face each other (hammer curl). Curl one arm at a time so each rep is counted cleanly.
Can I do bicep curls without weights?
Yes — water bottles, a backpack, resistance bands, or slow bodyweight tension all work. REP RUSH counts the curling motion whether or not you're holding a weight.
How many bicep curls should I do?
A common target is 3–4 sets of 8–12 reps, a few times per week. Give your arms a rest day between sessions to recover.
Do bicep curls build bigger arms?
Combined with progressively heavier weight over time and enough protein, curls are one of the most direct ways to build the biceps.
Count your reps, hands-free
REP RUSH watches through your webcam and counts every bicep curls rep on-device — no wearables, no signup, and your video never leaves your machine.
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